Concrete construction



P 1929. N. c. JOHNSON 1,728,936.

CONCRETE CONSTR UCTION Filed Aug. 25, 1926 anveutoz Mil/M12 a-fafinsam $3M in elf team Patented Sept. 24, 1929 NATHAN C. JOHNSON, OF ENGLEWOOD, NEW JERSEY CONCRETE CONSTRUCTION Application filed August 25, 1926.

This invention relates to concrete construction and more particularly to improvements in insulated concrete walls and the like.

As has long been known, a body of con- :3 crete readily transmits heat to a degree which renders uninsulated concrete very unsatisfactory for most building construction. Although walls made of solid concrete are not unsatisfactory by reason of the mere radiation of heat or the excessive absorption of heat, yet the heat transmission is such that moisture in the interior of a concrete building condenses on the walls unless they are insulated in some manner. The cost of insulat- 5 ing concrete walls by the methods heretofore known has been prohibitive of such constructions in most cases, yet in practice it is essential to eliminate such condensation, or sweating which is destructive, unsightly,

and troublesome.

It is an object of this invention to accomplish the insulation of concrete structures for the purposes above indicated in an economical and convenient manner and according to a practice adapted to a wide variety of concrete building constructions.

Various other specific objects, features and advantages will more clearly appear from the detailed description given below taken in connection with the accompanying drawing which forms a part of this specification.

In the drawing, the figure is an edge view illustrating one example of the invention. In order to avoid the undesirable condensation above referred to, according to this invention a concrete wall may be readily inst!- lated by providing dead air spaces in the structure. A body of concrete such as a wall 5, as indicated in the drawing, may be first cast in the conventional manner except that during its formative stage, or thereafter, at least one face thereof is coarsely roughened either by mechanical or a chemical treatmen In the preferred embodiment of the invention I provide this roughened surface by the use of the method and composition for treating concrete surfaces as disclosed in my Patent No. 1,637,321, dated July 26, 1927, application filed June 17, 1925. According to that invention the surface layer of the concrete is Serial No. 131,535.

rendered unsound by applying to the forms in which the concrete is poured a reagent for modifying the setting of the cement. Then after the forms are removed, the surface layers of the cement may be readily brushed or washed. away, leaving the coarse rough projecting aggregate exposed, as indicated at 6 in the drawing.

After the surface of the body of concrete has been thus roughened, suitable areas of building board or fibrous plaster board, as indicated at 7.,paper-backed lath and or other backings common in the building art, may be applied and fixed in place as by a bituminous or other water resisting or waterproof cement. Mechanical fastening means may obviously be used also. For example, asphalt or asphalt compositions may be painted upon the roughened surface to form an irregular layer, as indicated at 8. Then an area of the building board having an even or plane surface may be pressed against the raised or projecting areas 9 of the aggregate, and securely fixed in such position by the cement vVith this construction it is apparent, as shown in the drawing, that interstices or air cells 10 of substantial size will be provided beneath the building board and between the projecting aggregate particles. These spaces will be irregular in area and size, but will be found to extend over at least the major part of the concrete surface area. Furthermore, at irregular intervals the spaces will be dii-ded up by the projecting particles as cemented to the building board and accordingly in effect a cellular wall structure is provided by simple means and at a very low cost. The heat insulating efficiency of this construction is very great, inasmuch as the spaces are subdivided into a very large number of small dead air cells sealed by the ad hesive cement. Upon the exterior of the wall board suitable plaster or other finishing surface material 11 may be applied. Such plaster will of course serve to seal any cracks or crevices between the various sections or areas of building board, thus insuring also a proper sealing of the air spaces along lines where the sections of building board join, as well as over the remaining areas. In view of the insulating efficiency of the wall, the finished surface will be preserved without danger of any staining or deterioration resulting from moisture condensation. Accordingly the former disadvantages of concrete walls which in many cases have prohibited their use are by this invention entirely eliminated by a practical construction.

While I have described my invention according to the preferred embodiments .of the same, it will be obvious to those skilled in the art after understanding my invention that various alterations, modifications and substitutions may be made without departing from the scope of the invention and I aim in the appended claims to cover all such modifications.

lVhat is claimed as new and is desired to be secured by Letters Patent is:

1. A cellular wall structure comprising a body of concrete, one surface area of which is roughened, and a layer of building material secured thereon and having a substantially even surface area contacting with said roughened area but only at the high points thereon, whereby heat insulating air cells are provided between said surface areas.

2. A cellular wall structure comprising a body of concrete, one surface area of which is coarsely roughened, and a layer of building material secured thereon and having a substantially plane surface area secured by an adhesive to said roughened area but only at the high points thereon, whereby heat insulating air cells are provided between said surface areas. V

3. A cellular wall structure comprising a body of solid concrete, one surface area of which is roughened, and a layer of building material secured thereon by waterproof cement and having a substantially even surface area contacting with said roughened area but only at the high points thereon, whereby heat insulating air cells are provided between said surface areas.

f. A structure for the described purposes comprising a concrete body having a surface with projecting aggregate and covered with bituminous cement, and an area of building board or other material with a fibrous substantially plane surface secured to the projecting aggregate particles of said body by said cement, whereby heat insulating air cells are provided by interstices between such particles and whereby the cells are sealed waterproof by the bituminous cement.

5. A wall construction comprising a body of concrete, a surface thereof being chemically treated to removed the surface layers of cement leaving the projecting aggregate only, and an area of building board secured to projecting areas of said aggregate for the purposes described.

6. The method of constructing a building wall with insulating air cells therein, which comprises casting a body of concrete, providing the surface thereof with a series of peaks and depressions, and then applying a substantially even la er of building material in contact with said peaks, leaving air cells at the wall surface by reason of spaces between irregular aggregate particles and said even layer.

7. The method of constructing a wall with insulated air cells therein which comprises casting a body of concrete, producing a series of peaks and depressions in a surface thereof by inhibiting the set of said concrete at said surface and removing the unset surface when the remainder of the concrete has set, and then applying a layer of building material to cover said surface and contact with said peaks whereby insulating air cells are provided between the inner surface of the building material and the faces of said depressions.

In testimony whereof I have signed my name to this specification.

NATHAN C. JOHNSON. 

